The present invention relates to clockworks and timepieces and, more particularly, to a mechanism for aligning or synchronizing the hands in an analog timepiece.
A typical analog timepiece, such as a clock, includes a housing providing a clock face or dial having time indicators, a plurality of hands rotatably supported on the clock face and positionable relative to the indicators to indicate a time, and an analog clockworks for controlling the position and movement of the hands. The clockworks includes a mechanism for setting the hands in respective rotational positions to indicate a time and a drive mechanism supported by the housing and connectable to the hands to rotatably drive the hands. The drive mechanism is connectable to a power source, such as a AA battery, which is operable to power the drive mechanism.
The clock industry has developed a standard size for a quartz analog clockworks unit. The standard-sized unit is 56 mm wide by 56 mm high by 17 mm thick. In this unit, the battery is located horizontally at the bottom of and is accessible from the back of the unit. Output shafts of the drive mechanism are centrally located on the front side of the unit. The standard unit also has two ledges (15 mm wide), one on the top of the unit and the other on the bottom of the unit. The ledges enable the unit to be snapped into the clock housing and held in place. This snap-in feature is used by most major clock companies as part of the clock assembly process.
For a standard analog timepiece, a mechanism is required for the initial alignment or positioning of the hands relative to the indicators on the face so that the hands display the correct time. Typically, this mechanism is a mechanical set button which adjusts the positions of the hands relative to the indicators. After the initial positioning or setting of the hands, the regulated drive mechanism moves the hands so that the hands continue to display the correct time.
Another type of analog timepiece is a remotely- controlled (i.e., radio-controlled) analog timepiece. Such a clock includes a clockworks capable of driving the hands to display a time corresponding to a broadcast time signal. To do so, this clockworks typically includes a drive mechanism for driving the hands, a receiver for receiving the broadcast time signal, means for comparing information corresponding to a broadcast time represented by the broadcast time signal to information corresponding to the local time indicated by the hands, and means for synchronizing the time indicated by the hands to the broadcast time.
For the remotely-controlled timepiece to display the correct time, a mechanism is required to align or synchronize the respective positions of the hands (the local time) with electronic information corresponding to these positions. In general, these remotely-controlled timepieces may be fully-automatic (no operator adjustment required to align the hands) or semi-automatic (some operator adjustment required to align the respective positions of the hands with the electronic information corresponding to these positions).
U.S. Pat. No. 5,231,612, which issued to Allgaier et al., discloses a radio-controlled timepiece including a fully-automatic mechanism for the detection and correction of a hand setting. The mechanism includes components for sending and receiving a radiation beam, respectively. A hand setting mechanism includes an hour wheel, a minute wheel and a seconds wheel, each having an aperture. The hour wheel has a front mirror for reflecting the beam to the receiver. The beam to a rear mirror is passed through the front mirror to such that the beam is reflected by the rear mirror only after passing through the aligned apertures and discs. With this mechanism, the position of the hands may be automatically determined and corrected.
U.S. Pat. No. 5,671,192, which issued to Schaffel, discloses a semi-automatic radio-controlled, analog display clockworks. The clockworks includes a hand or pointer setting arrangement for the user to bring the pointers to a predetermined position corresponding to a certain time. Starting from this predetermined position, the control device applies control signals to the drive arrangement, causing the pointers to move more quickly until they are in a position corresponding to the broadcast time represented by the broadcast time signal.